This set consisting of: * Pre-motor filter (blue / blue) * HEPAAllergy post-motor filter (blue / white) Characteristics of theVormotorfilters: * Washable * Filters out even the smallest particles * should be min. every 6 months are washed * as for Dyson-No.: 917819-01 * not original but Dyson manufactured to exacting standards in size and feature high-quality alternative product Mekrmale ofHEPAAllergy Nachmotorfilters: * Filters out even the smallest particles * Highly recommended for allergy sufferers * Do not wash * as for Dyson-No.: 900228-01 * not original but Dyson manufactured to exacting standards in size and feature high-quality alternative product Installation: Pre-motor filter(Washable filter) The washable pre-motor filter is located on the rear end of the Dyson Pull the nose up and lift the lid. HEPAAllergy post-motor byHEPAAllergy post-motor filter is located under the transparent dust container. The nose in the direction of arrow out and raise the lid.